My neon is a 99 dohc atx. It started stalling one day but it would start rite up and would sometimes stall again. I took it to a mechanic who couldn't find any cause for the stalling but told me to replace the fuel pump. I didn't replace the pump It has good psi so I replaced the fuel pump relay and asd relay but they didn't fix the problem. The car kept stalling for a week then one morning it wouldn't start so I replaced the coil, crank position sensor, cam position sensor, spark plugs, timing belt, not the plug wires they are only 2 months old so I didn't change them but it still wouldn't start so I replaced the pcm and it started rite up. The codes it had when it died were 11,12,21,37.
Now it has started all over again the codes I get now are 12,21,37,43. I got it to start the next day and got it home but now i'm worried that it's going to fry the pcm again if it hasn't yet. Can any of you make any sense of this I sure can't?

i had a similar problem when i changed my timing belt. one tooth off wont stop it from rinning but it wont run right. i was getting the crank sensor code and the timing code. i repositioned the timing belt and all is well. i havent seen the cel now in 3 months.

on another note changing the pcm will not get rid of the code 11. been there done that. just reposition the timing belt but make sure you pull the plugs in the process so theres no compression in the head. its pretty easy to set it one tooth off.

When I replaced the timing belt I made sure all the timing marks were lined up exactly rite. After replacing the timing belt I checked the coil driver circuits from the pcm and found one of them was grounded by the pcm. It lit up as soon as I connected the test lite, it was suposed to blink only when the engine was cranking. The other wire blinked like it should so I traced the bad one to the pcm and replaced the wire to be sure that it wasn't shorted but it was still grounded by the pcm. I don't get code 11 now it went away after I replaced the sensors and timing belt my current codes are 12,37,43,21. My Haynes manual list code 43 as multiple or single missfire detected/peak primary circuit current not achieved with the maximum dwell time. My obd2 gave a different code for it but it said Ingition coil B primary/secondary circuit malfunction ignition coil #2 ckt.

my car check engine light does not flash to give a code but i get a code where the miles show up at i got code P420,P0300, i cant find where to look the codes up at. the problem with my car is when i am driving and i push the pedal down fast the car starts cuting out and sputtering it.